UE4-Plugin-OffAxis

Current version

• Works with 4.23 :)
• check out the branch "UE5" with info on how to run it for UE5

General info:

It works. But it is (always) experimental :)

• OffAxisProjection / FishTank VR
  • in 2D Mode: OffAxisActor can be placed arbitrarily.
  • in 3D Mode: OffAxisActor can be translated in x,y, z and rotated using pitch and roll.
• Also shows a possibility of how to modify the projection matrix.

How to use:

Assuming you start with a new project:

• If your project is a C++ project, you are good to go. If you have a pure blueprint project, add a random C++ class via File -> Add C++ class (empty class is fine).
• Copy the Plugin in your (you might need to create a Plugin folder in the directory where your uproject file is).
• Start (or restart) Unreal Engine. You might get a warning that the plugin needs to be rebuild. That's normal.
• Update LocalPlayer class in Edit->Project Settings->General Settings
• Adjust Input mappings to your Config/DefaultInput.ini (just copy the below mappins to your Config/DefaultInput.ini. If you don't have one, create a random new mapping in Settings --> Project Settings --> Input. Then the file should be there. Then copy the mappings. Restart UE4.
• Drag the OffAxisActor in your scene
• Set position of OffAxisActor to 0,0,0
• In the OffAxisActor, place the child actors P_a, P_b, and P_c so that the correspond to the corners of your "virtual window".
• Change your NearClippingPlane .1f (Settings --> Project Settings --> Engine --> General Settings --> Near Clip Plane)
• Select the OffAxisActor in your Project Outliner: set "Use Off Axis on Start" to true and change "Tracking Device" to None (the Set Tracking Device Setting is still in early stages).
• Hit play. If it is not working now, close UE4, right-click on your uproject file and regenerate Visual Studio Project Files, try again :)
• If it starts but the screen is black, try to either move the STartPositionEye of the OffAxisActor along X or (if you have copied the input mappings) play around with pageUp and pageDown.

Input Mappings

• Here are the current input mappings the plugin supports/uses. Just copy and paste this bunch in your DefaultInput.ini and restart after updating DefaultInput.ini!
• For some inputs, you might need to change the key if they are already in use in your project.

OffAxis

+ActionMappings=(ActionName="HomePosReset",bShift=True,bCtrl=False,bAlt=False,bCmd=False,Key=Home) +ActionMappings=(ActionName="ResetEyeOffset",bShift=True,bCtrl=False,bAlt=False,bCmd=False,Key=Nine) +ActionMappings=(ActionName="ResetProjectionPlaneOffset",bShift=True,bCtrl=False,bAlt=False,bCmd=False,Key=Six) +ActionMappings=(ActionName="ToggleShowDebugMessages",bShift=True,bCtrl=False,bAlt=False,bCmd=False,Key=V) +ActionMappings=(ActionName="ToggleUseOffAxis",bShift=True,bCtrl=False,bAlt=False,bCmd=False,Key=P) +ActionMappings=(ActionName="Pick",bShift=False,bCtrl=False,bAlt=False,bCmd=False,Key=LeftMouseButton) +ActionMappings=(ActionName="ToggleVisOffAxisMenu",bShift=False,bCtrl=False,bAlt=False,bCmd=False,Key=F9) +AxisMappings=(AxisName="EyeUp",Scale=1.500000,Key=Up) +AxisMappings=(AxisName="EyeUp",Scale=-1.500000,Key=Down) +AxisMappings=(AxisName="EyeLeft",Scale=-1.500000,Key=Left) +AxisMappings=(AxisName="EyeLeft",Scale=1.500000,Key=Right) +AxisMappings=(AxisName="EyeForward",Scale=1.000000,Key=PageUp) +AxisMappings=(AxisName="EyeForward",Scale=-1.000000,Key=PageDown) +AxisMappings=(AxisName="Pick_away",Scale=0.100000,Key=W) +AxisMappings=(AxisName="Pick_left",Scale=-0.100000,Key=A) +AxisMappings=(AxisName="Pick_down",Scale=0.100000,Key=Q) +AxisMappings=(AxisName="Pick_away",Scale=-0.100000,Key=S) +AxisMappings=(AxisName="Pick_left",Scale=0.100000,Key=D) +AxisMappings=(AxisName="Pick_down",Scale=-0.100000,Key=E) +AxisMappings=(AxisName="Wheel",Scale=1.000000,Key=MouseWheelAxis) +AxisMappings=(AxisName="MouseX",Scale=1.000000,Key=MouseX) +AxisMappings=(AxisName="MouseY",Scale=1.000000,Key=MouseY) +AxisMappings=(AxisName="ChangeProjectionPlaneOffset",Scale=0.100000,Key=Five) +AxisMappings=(AxisName="ChangeProjectionPlaneOffset",Scale=-0.100000,Key=Six) +AxisMappings=(AxisName="MoveUp",Scale=0.100000,Key=I) +AxisMappings=(AxisName="MoveDown",Scale=-0.100000,Key=K) +AxisMappings=(AxisName="MoveLeft",Scale=-0.100000,Key=J) +AxisMappings=(AxisName="MoveRight",Scale=0.100000,Key=L) +AxisMappings=(AxisName="Away",Scale=0.100000,Key=U) +AxisMappings=(AxisName="Towards",Scale=-0.100000,Key=O) +AxisMappings=(AxisName="ChangeEyeOffset",Scale=0.001000,Key=Seven) +AxisMappings=(AxisName="ChangeEyeOffset",Scale=-0.010000,Key=Eight)

Optitrack related:

+ActionMappings=(ActionName="TryToConnectToServer",bShift=True,bCtrl=False,bAlt=False,bCmd=False,Key=One) +ActionMappings=(ActionName="ConnectToOptitrack",bShift=True,bCtrl=False,bAlt=False,bCmd=False,Key=Y)

Based on...

http://nttl.ru/en

https://perspectiveresources.blogspot.de/2013/04/i3d-head-coupled-perspective.html

http://iihm.imag.fr/en/demo/hcpmobile/

https://www.youtube.com/watch?v=hvrT7FqpPQE

https://www.youtube.com/watch?v=-foNLFnrNRc

https://www.youtube.com/watch?v=PP38yj3zdqo

https://www.youtube.com/watch?v=5ibPBGCAWKo

http://csc.lsu.edu/~kooima/articles/genperspective/

Michael Deering. 1992. High resolution virtual reality. ACM SIGGRAPH Computer Graphics 26, 2: 195–202. https://doi.org/10.1145/142920.134039

https://answers.unrealengine.com/questions/65003/howto-modify-the-projection-matrix.html